The goal of this Mentored Patient-Oriented Research Career Development Award (K23) is to support Dr. Nicole Ennis Whitehead, a Clinical Psychologist, in developing the critical skills necessary to become an independent researcher in the implementation of substance use interventions in real world settings. She seeks to acquire skills in: 4 areas: substance use intervention science, implementation science, mixed methods, and research conduct Both the National Institute on Drug Abuse (NIDA) and the Office of AIDS Research (OAR) have prioritized research that promotes the uptake of evidence based interventions into real-world settings. Extant literature indicates that 20-50% of those aging with HIV misuse alcohol, illicit drugs or prescription medications. Interventions that reach this population are needed. To date many effective interventions do not translate into meaningful outcomes that improve patient care. Substance use interventions in particular have lagged in moving from research laboratories to real-world settings (primary care clinics, community treatments centers, etc.). The Screening, Brief Intervention and Treatment (SBIRT) model has been effective in decreasing high risk behaviors such as tobacco, alcohol, and illicit drug use. However, recent data suggests that brief intervention models alone may not be effective with vulnerable populations. The evidence supporting SBIRT indicates that other models such as SBIRT with a peer navigator (SBIRT-PN) should be examined for this population. Therefore, the training goal for this K23 is to advance the candidate's skills in implementing SBIRT-PN in HIV primary care clinics for HIV+ adults 50 and older. Training aims include: (1) Describe and differentiate optimal methods of substance use intervention with vulnerable populations; (2) Obtain skills to implement substance use interventions in real-world settings; and (3) Acquire skills in advanced intervention modeling and mixed methods research and use these methods to evaluate substance use interventions. Execution of these research aims along with a comprehensive training program will be led by Dr. Robert Cook, Dr. Linda B. Cottler and Dr. Xinguang Chen with additional collaborators to address training specific needs. The research project will use the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to pilot and evaluate the SBIRT-PN using the Southern HIV and Alcohol Research Consortium (SHARC) HIV primary care clinic network. Aim 1: Pilot effectiveness of SBIRT-PN versus treatment as usual in HIV primary care clinics to improve substance-use treatment engagement and HIV appointment adherence among adults aged 50 and older. Aim 2: Describe the influence of demographic factors, depression and pain on substance-use treatment engagement outcomes. Aim 3: Examine and enhance feasibility (recruitment, dose, retention) of intervention uptake for a larger trial. The proposed research will provide the preliminary data needed to support an R01 testing the implementation of this intervention (SBIRT-PN) across a broad clinical network serving older HIV+ adults. Completion of this plan will prepare me for a career as an independent clinical investigator trained to implement substance use interventions in real world settings.